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141.
Controlling effective interactions and spatial dispersion of nanoparticles in multiblock copolymer melts 下载免费PDF全文
Debapriya Banerjee Kenneth S. Schweizer 《Journal of Polymer Science.Polymer Physics》2015,53(16):1098-1111
The microscopic Polymer Reference Interaction Site Model theory is employed to study, for the first time, the effective interactions, spatial organization, and miscibility of dilute spherical nanoparticles in non‐microphase separating, chemically heterogeneous, compositionally symmetric AB multiblock copolymer melts of varying monomer sequence or architecture. The dependence of nanoparticle wettability on copolymer sequence and chemistry results in interparticle potentials‐of‐mean force that are qualitatively different from homopolymers. An important prediction is the ability to improve nanoparticle dispersion via judicious choice of block length and monomer adsorption‐strengths which control both local surface segregation and chain connectivity induced packing constraints and frustration. The degree of dispersion also depends strongly on nanoparticle diameter relative to the block contour length. Small particles in copolymers with longer block lengths experience a more homopolymer‐like environment which renders them relatively insensitive to copolymer chemical heterogeneity and hinders dispersion. Larger particles (sufficiently larger than the monomer diameter) in copolymers of relatively short block lengths provide better dispersion than either a homopolymer or random copolymer. The theory also predicts a novel widening of the miscibility window for large particles upon increasing the overall molecular weight of copolymers composed of relatively long blocks. The influence of a positive chi‐parameter in the pure copolymer melt is briefly studied. Quantitative application to fullerenes in specific copolymers of experimental interest is performed, and miscibility predictions are made. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1098–1111 相似文献
142.
Colloid Journal - An Erratum to this paper has been published: https://doi.org/10.1134/S1061933X21330024 相似文献
143.
Yuyang Ji Rebekka S. Klausen 《Journal of polymer science. Part A, Polymer chemistry》2021,59(21):2521-2529
The synthesis of vinyl alcohol copolymers is limited due to the poor radical reactivity of vinyl acetate (VAc), the traditional precursor to polyvinyl alcohol (PVA). Main group monomers such as BN 2-vinylnaphthalene (BN2VN) have attracted attention as alternatives to VAc to form side chain hydroxyls via oxidation, but outstanding questions of molecular weight control remain. Herein we report systematic investigation of solvent, temperature, and initiator concentration as factors influencing BN2VN degree of polymerization. We find increased chain transfer to toluene, hypothesized to arise from differences in radical stabilization and reactivity by aromatic and BN aromatic rings. As a result of these combined efforts, high molecular weight (Mw ~ 105 g mol−1) BN2VN homopolymers and BN2VN-styrene copolymers were obtained. 相似文献
144.
Farsi R. Mohammadi M. K. Saghanezhad S. J. 《Russian Journal of Organic Chemistry》2021,57(12):2002-2009
Russian Journal of Organic Chemistry - Herein, we report the sulfonamide-functionalized covalent organic framework (COF-SO3H), prepared by condensation of melamine and terephthalaldehyde and... 相似文献
145.
Vyacheslav V. Sentyurin Oleg A. Levitskiy Tatiana V. Magdesieva 《Current Opinion in Electrochemistry》2020
This mini-review highlights key structural features that should be taken into account when creating ambipolar redox-active closed-shell metal-free molecules. This type of compound is strongly required for the fabrication of all-organic ‘poleless’ batteries and semiconductors. The suggested strategies aimed at stabilization of both oxidized (cationic) and reduced (anionic) redox-states are based on the comprehensive analysis of the most successful structures taken from the recent publications. 相似文献
146.
Transport in Porous Media - A macroscopic model that accounts for the effect of momentum dispersion on flows in porous media is proposed. The model is based on the pore scale prevalence hypothesis... 相似文献
147.
Vereshchagin Anatoly N. Karpenko Kirill A. Elinson Michail N. Minaeva Alexandra P. Goloveshkin Alexander S. Hansford Karl A. Egorov Mikhail P. 《Molecular diversity》2020,24(4):1327-1342
Molecular Diversity - A novel five-component diastereoselective synthesis of polysubstituted 2-piperidinones is reported. The Knoevenagel condensation–Michael addition–Mannich cascade... 相似文献
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